After increasing the hard drive size in the hypervisor, when trying to extend the disk volume on an MCS machine catalog VM, the Extended Volume option greyed out.

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The only way to move the Recovery partition is using a third party tool. There are several disk partition assistant tools, like AOMEI and NIUBI.

In this article, we used AOMEI and followed instructions on https://www.disk-partition.com/blog/move-unallocated-space-to-the-left-or-right-side-4125/.

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Problem Cause

Disk Management can only support Extend Volume on a partition using an unallocated space adjacent to it at the right side. In this case, the C:\ volume cannot be extended because there is another partition, a Recovery partition,  between it and the unallocated space.

AOMEI Partition Assistant Standard Edition - https://www.disk-partition.com/free-partition-manager.html

NIUBI Partition Editor - https://www.hdd-tool.com/windows-10/how-to-merge-unallocated-space.html